The present invention relates to inserts used to make void spaces in a cast material, such as in precast concrete panels, and more particularly for use in setting and protecting engineered lifting systems that are to be embedded within the precast concrete panels.
Prestressed, precast concrete panels are widely popular in the building and construction industry. Large, heavy concrete panels typically require a lifting element(s) to be embedded within the panel so they can be readily moved, and arranged at the construction site. It has been a past practice to provide inserts that are positionable within the concrete panels prior to casting, to thereby form holes, depressions, or other desired geometrical void configurations, within the panels once the concrete has cured.
Inserts have also been used in conjunction with engineered lifting systems, where the inserts are to be permanently embedded within the concrete panels. The inserts in that application are designed to hold or support the lifting system as the concrete cures, and to leave a depression in the cured panel which facilitates access to the lifting system so that lifting hooks and/or cables can be directly connected to the lifting system without interference from part of the concrete panel.
Setting of an insert typically involves the use of pins and various angle-iron supports to position the inserts in a desired location and to facilitate removal of the inserts with a minimum of difficulty. However, there are several existing problems related to the inserts presently available; some inserts are not easily positionable; others fail or inadequately protect the lifting system during casting; many are difficult to remove after the concrete has cured; most inserts have a very low level of reusability. The removal and reusability problems are very much related, in that typically, the insert assembly will become bonded to the concrete, making the removal both time consuming and difficult, and usually destroying the integrity of the insert so that it cannot be used again. Some damage may even result to the casting itself.
It can be appreciated that based on the above-described problems, there still exists a long-felt need to provide a concrete insert which can overcome the difficulties and problems mentioned above.
It is a primary aspect of the invention to provide an improved insert that is to be used in connection with an element or assembly where the latter is to be permanently set within the casting. The insert of the present invention thus comprises in one embodiment, a base assembly having an exterior surface defining the shape of the void space to be created, with an interior space having an opening through which the element extends, an access opening through which the interior space is accessed, and a cover over the access opening which closes and protects the interior space, and the element extending therein. In a preferred embodiment, the base assembly, the interior space and the bottom opening are adapted for temporarily receiving a lifting element, such as a hook, that is to be set into a precast concrete panel, and a lid for protecting the interior space of the base assembly.
It is another aspect of the invention to provide an insert wherein the base assembly is non-destructibly removable from the cast material. This reusable insert advantageously includes a pair of movable flaps for assisting removal of the insert after the cast material is set.
It is yet another aspect of the invention to provide an insert assembly wherein the lid is provided with at least one, and preferably a pair of spaced holes, each hole for receiving a positioning plate therethrough for positioning of the insert.
It is still another aspect of the invention to provide an insert assembly wherein the lifting mechanism utilizes a rod, and the insert includes arcuate wall brackets integrally formed therein for receiving the rod of the lifting hook assembly that is to be set into the panel.